Lack of evidence for sufficiently isolated populations of Glossina morsitans submorsitans on the Adamawa Plateau of Cameroon following geometric morphometric analysis

Abstract

Trypanosomosis remains the number one killer of livestock in spite of efforts made to eradicate tsetse flies in the Adamawa plateau of Cameroon. Acetone-baited Laveissière type biconical traps were pitched at 100 meter intervals in strategic geo-referenced positions in various ecological niches of the landscape for 5 consecutive days in selected villages in Mayo Rey, Mbere, Vina and Faro et Deo divisions. All 493 tsetse flies captured in sites other than Mboula were G. morsitans submositans. Measurement of dif- ferent morphometric characters on the wings of each individual fly was undertaken using the Du Jardin package. The data was processed and analysed by “Permutaciones, Analisis Discrimi- nante (PAD)” and “Bootstraps, Analisis en Com- ponentes principales”. The three major sam- pling sites on the plateau yielded similar results as demonstrated by the neighbour joining tree of Mahalanobis distances but tests using PAD showed the differences between group means to be significant (P < 0.05) even when the same number of flies was used. Mixing of tsetse populations from the northern lowlands and those on the plateau and Koutine plain could not be ruled out. These preliminary findings suggest that the flies are not from isolated populations and should be considered as populations fre- quently exchanging migrants. However, mo- lecular genetics techniques are necessary in ad- dition to morphometric analysis to reach more definitive conclusions.